1/*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
4 *           (C) 2001 Dirk Mueller (mueller@kde.org)
5 * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public License
18 * along with this library; see the file COPYING.LIB.  If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 *
22 */
23
24#ifndef LiveNodeList_h
25#define LiveNodeList_h
26
27#include "CollectionType.h"
28#include "Document.h"
29#include "HTMLNames.h"
30#include "NodeList.h"
31#include <wtf/Forward.h>
32#include <wtf/RefPtr.h>
33
34namespace WebCore {
35
36class Element;
37
38enum NodeListRootType {
39    NodeListIsRootedAtNode,
40    NodeListIsRootedAtDocument,
41    NodeListIsRootedAtDocumentIfOwnerHasItemrefAttr,
42};
43
44class LiveNodeListBase : public NodeList {
45public:
46    enum ItemAfterOverrideType {
47        OverridesItemAfter,
48        DoesNotOverrideItemAfter,
49    };
50
51    LiveNodeListBase(Node* ownerNode, NodeListRootType rootType, NodeListInvalidationType invalidationType,
52        bool shouldOnlyIncludeDirectChildren, CollectionType collectionType, ItemAfterOverrideType itemAfterOverrideType)
53        : m_ownerNode(ownerNode)
54        , m_cachedItem(0)
55        , m_isLengthCacheValid(false)
56        , m_isItemCacheValid(false)
57        , m_rootType(rootType)
58        , m_invalidationType(invalidationType)
59        , m_shouldOnlyIncludeDirectChildren(shouldOnlyIncludeDirectChildren)
60        , m_isNameCacheValid(false)
61        , m_collectionType(collectionType)
62        , m_overridesItemAfter(itemAfterOverrideType == OverridesItemAfter)
63        , m_isItemRefElementsCacheValid(false)
64    {
65        ASSERT(m_rootType == static_cast<unsigned>(rootType));
66        ASSERT(m_invalidationType == static_cast<unsigned>(invalidationType));
67        ASSERT(m_collectionType == static_cast<unsigned>(collectionType));
68        ASSERT(!m_overridesItemAfter || !isNodeList(collectionType));
69
70        if (collectionType != ChildNodeListType)
71            document()->registerNodeList(this);
72    }
73
74    virtual ~LiveNodeListBase()
75    {
76        if (type() != ChildNodeListType)
77            document()->unregisterNodeList(this);
78    }
79
80    // DOM API
81    virtual unsigned length() const OVERRIDE;
82    virtual Node* item(unsigned offset) const OVERRIDE;
83
84    ALWAYS_INLINE bool hasIdNameCache() const { return !isNodeList(type()); }
85    ALWAYS_INLINE bool isRootedAtDocument() const { return m_rootType == NodeListIsRootedAtDocument || m_rootType == NodeListIsRootedAtDocumentIfOwnerHasItemrefAttr; }
86    ALWAYS_INLINE NodeListInvalidationType invalidationType() const { return static_cast<NodeListInvalidationType>(m_invalidationType); }
87    ALWAYS_INLINE CollectionType type() const { return static_cast<CollectionType>(m_collectionType); }
88    Node* ownerNode() const { return m_ownerNode.get(); }
89    ALWAYS_INLINE void invalidateCache(const QualifiedName* attrName) const
90    {
91        if (!attrName || shouldInvalidateTypeOnAttributeChange(invalidationType(), *attrName))
92            invalidateCache();
93        else if (hasIdNameCache() && (*attrName == HTMLNames::idAttr || *attrName == HTMLNames::nameAttr))
94            invalidateIdNameCacheMaps();
95    }
96    void invalidateCache() const;
97    void invalidateIdNameCacheMaps() const;
98
99    static bool shouldInvalidateTypeOnAttributeChange(NodeListInvalidationType, const QualifiedName&);
100
101protected:
102    Document* document() const { return m_ownerNode->document(); }
103    Node* rootNode() const;
104    ContainerNode* rootContainerNode() const;
105    bool overridesItemAfter() const { return m_overridesItemAfter; }
106
107    ALWAYS_INLINE bool isItemCacheValid() const { return m_isItemCacheValid; }
108    ALWAYS_INLINE Node* cachedItem() const { return m_cachedItem; }
109    ALWAYS_INLINE unsigned cachedItemOffset() const { return m_cachedItemOffset; }
110
111    ALWAYS_INLINE bool isLengthCacheValid() const { return m_isLengthCacheValid; }
112    ALWAYS_INLINE unsigned cachedLength() const { return m_cachedLength; }
113    ALWAYS_INLINE void setLengthCache(unsigned length) const
114    {
115        m_cachedLength = length;
116        m_isLengthCacheValid = true;
117    }
118    ALWAYS_INLINE void setItemCache(Node* item, unsigned offset) const
119    {
120        ASSERT(item);
121        m_cachedItem = item;
122        m_cachedItemOffset = offset;
123        m_isItemCacheValid = true;
124    }
125    void setItemCache(Node* item, unsigned offset, unsigned elementsArrayOffset) const;
126
127    ALWAYS_INLINE bool isItemRefElementsCacheValid() const { return m_isItemRefElementsCacheValid; }
128    ALWAYS_INLINE void setItemRefElementsCacheValid() const { m_isItemRefElementsCacheValid = true; }
129
130    ALWAYS_INLINE NodeListRootType rootType() const { return static_cast<NodeListRootType>(m_rootType); }
131
132    bool hasNameCache() const { return m_isNameCacheValid; }
133    void setHasNameCache() const { m_isNameCacheValid = true; }
134
135    bool shouldOnlyIncludeDirectChildren() const { return m_shouldOnlyIncludeDirectChildren; }
136
137private:
138    Node* itemBeforeOrAfterCachedItem(unsigned offset, ContainerNode* root) const;
139    Node* traverseChildNodeListForwardToOffset(unsigned offset, Node* currentNode, unsigned& currentOffset) const;
140    Element* traverseLiveNodeListFirstElement(ContainerNode* root) const;
141    Element* traverseLiveNodeListForwardToOffset(unsigned offset, Element* currentElement, unsigned& currentOffset, ContainerNode* root) const;
142    bool isLastItemCloserThanLastOrCachedItem(unsigned offset) const;
143    bool isFirstItemCloserThanCachedItem(unsigned offset) const;
144    Node* iterateForPreviousNode(Node* current) const;
145    Node* itemBefore(Node* previousItem) const;
146
147    RefPtr<Node> m_ownerNode;
148    mutable Node* m_cachedItem;
149    mutable unsigned m_cachedLength;
150    mutable unsigned m_cachedItemOffset;
151    mutable unsigned m_isLengthCacheValid : 1;
152    mutable unsigned m_isItemCacheValid : 1;
153    const unsigned m_rootType : 2;
154    const unsigned m_invalidationType : 4;
155    const unsigned m_shouldOnlyIncludeDirectChildren : 1;
156
157    // From HTMLCollection
158    mutable unsigned m_isNameCacheValid : 1;
159    const unsigned m_collectionType : 5;
160    const unsigned m_overridesItemAfter : 1;
161    mutable unsigned m_isItemRefElementsCacheValid : 1;
162};
163
164ALWAYS_INLINE bool LiveNodeListBase::shouldInvalidateTypeOnAttributeChange(NodeListInvalidationType type, const QualifiedName& attrName)
165{
166    switch (type) {
167    case InvalidateOnClassAttrChange:
168        return attrName == HTMLNames::classAttr;
169    case InvalidateOnNameAttrChange:
170        return attrName == HTMLNames::nameAttr;
171    case InvalidateOnIdNameAttrChange:
172        return attrName == HTMLNames::idAttr || attrName == HTMLNames::nameAttr;
173    case InvalidateOnForAttrChange:
174        return attrName == HTMLNames::forAttr;
175    case InvalidateForFormControls:
176        return attrName == HTMLNames::nameAttr || attrName == HTMLNames::idAttr || attrName == HTMLNames::forAttr
177            || attrName == HTMLNames::formAttr || attrName == HTMLNames::typeAttr;
178    case InvalidateOnHRefAttrChange:
179        return attrName == HTMLNames::hrefAttr;
180    case InvalidateOnItemAttrChange:
181#if ENABLE(MICRODATA)
182        return attrName == HTMLNames::itemscopeAttr || attrName == HTMLNames::itempropAttr
183            || attrName == HTMLNames::itemtypeAttr || attrName == HTMLNames::itemrefAttr || attrName == HTMLNames::idAttr;
184#endif // Intentionally fall through
185    case DoNotInvalidateOnAttributeChanges:
186        return false;
187    case InvalidateOnAnyAttrChange:
188        return true;
189    }
190    return false;
191}
192
193class LiveNodeList : public LiveNodeListBase {
194public:
195    LiveNodeList(PassRefPtr<Node> ownerNode, CollectionType collectionType, NodeListInvalidationType invalidationType, NodeListRootType rootType = NodeListIsRootedAtNode)
196        : LiveNodeListBase(ownerNode.get(), rootType, invalidationType, collectionType == ChildNodeListType,
197        collectionType, DoesNotOverrideItemAfter)
198    { }
199
200    virtual Node* namedItem(const AtomicString&) const OVERRIDE;
201    virtual bool nodeMatches(Element*) const = 0;
202
203private:
204    virtual bool isLiveNodeList() const OVERRIDE { return true; }
205};
206
207} // namespace WebCore
208
209#endif // LiveNodeList_h
210